createRecentImageryPanel() computes the readout from the layer snapshot
and renders RecentImageryReadout and its day cards synchronously; its
delegated listeners stay on the stable root and the mode buttons keep their
segmented control. Rail card actions take optional pressed and reserved
states, replacing the owner's patches after render. Thumbnails, focus,
scroll preservation, the DETAILS reveal and export behave as before, and
nothing paints after teardown.